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Incident type - cleaning gear on the run

Incident 3. The plane went into the landing at a height below the calculated one. The air mechanic watched closely as the commander of the ship brought the plane to the ground. The commander of the ship at the required moment gave the command: "Rud-zero. The screws are on the stop. " Bortmehanik, continuing to observe the movement of the aircraft, removed the throttle, removed the chassis and reported to the commander: 'TUD-zero. The screws are removed. " After a while, the plane, when moving along the runway, began to drop onto the fuselage, producing "metallic" sounds. Bortmehanik first suggested that this was due to the fact that the wheels broke, and later, after discovering that the plane landed on the fuselage, suggested that there was a breakdown in the chassis system. And only then, paying attention to the controls and seeing that the chassis switch is in the "Cleaning" position, and the thumbscrew of the propellers is in the "On the stop" position, he realized that instead of removing the screws from the stop, he removed the chassis .

Making a really wrong procedure (using the chassis control element), the flight mechanic is sure that he performs the required (removes the screws from the stop), therefore, these two procedures at this moment for the flight engineer are indistinguishable. Thus, the basis of this error is not the distinction between two different procedures in fact. Qualification of this error as confusion means fixing only the external fact (at the moment when you need to remove the screws from the stop, the flight mechanic removes the chassis), in the internal plane of the subject there is no mistaking - he does exactly what he intends to do; Subjectively, he removes the screws from the stop. The phenomenon of certainty in executing one procedure in the performance of another is called a "phenomenon of non-discrimination," the occurrence of which was the cause of the error.

Using the concept of pseudo-action, this incident can be explained as follows. Bortmehanik received commands to remove the revolutions and remove the screws from the stop and performed them, carefully watching the landing process. But if you control the execution of the first command, you can and without interrupting the visual observation of the landing - by the noise of the engines, then you can check the execution of the second command only visually on the instruments. But since the visual channel was busy, and the procedure itself is trivial, the flight mechanic did not address the positioning of the screws, especially since the procedure for monitoring the landing and the procedure for removing the screws from the stop coincided with the time of completion: the screws were removed at the moment when the aircraft Was safely led to B1I1I. The lack of control over the result of the procedure means, as well as in the 2 incident, the lack of experience achieved by this procedure.

The implementation of the procedure for removing screws from the stop during the execution of another procedure - subjectively significant and actively experienced - means that the procedure for removing the screws had the status of an operation and was not represented by an independent experience of intention and achievement. Thus, the procedure for removing the screws was represented in the activity of the flight mechanic only as its moving part, while the observation was represented by a detailed experience, but in fact did not have its motor part. When conjoining the experience of one procedure, which does not have a motor component, and the motor part of another procedure,

not accompanied by the experience of its implementation, formed psevdodeystvie. The resulting pseudo-action refers to the procedure of removing the screws, because it must be carried out by the commander of the team, so the mechanic and report on its implementation.

The operational status of the procedure means that the links between its implementation and the experience of its implementation are weakened. The weakening of communication creates opportunities for a person not to notice the substitution of one procedure by another. This is what happened in this case: the flight mechanic did not realize that instead of the toggle switch, the Air screws used the switch "Chassis". The operation of one control instead of another in the case under consideration could be due to several factors. Firstly, there is very little difference in how these elements are involved: both elements lie in the same plane of the right hand movement and are actuated by very similar finger movements. Secondly, on takeoff after the transfer of the RUD, though to another, but also to the extreme position, the flight mechanic uses the switch "Chassis". Third, after completing the first part of the procedure (installing the throttle), the hand is next to the switch "Chassis". Thus, it can be stated with certainty that there is a similarity in the procedures for using both controls, which makes it possible to identify them in the mind. Obviously, any of the similar factors, as well as their composition, could provoke this error.

As for ignoring the warning information, the reasons are the same as that in the first two incidents.